Francis arthur mills



(No Model.)

P. A. MILLS. WAX THREAD HEATING DEVICE FOR SEWING MAUHINHS.-

No. 524,340. Patented Aug. 14, 1894.

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UNITED STATES P TENT" OFFI FRANCIS ARTHUR MILLS, OF PHILADELPHIA,PENNSYLVANIA, ASSIGNOR F ONE-HALF TO JAMES MUNDELL, OF SAME PLACE.

WAX-THREAD-HEA TING DEVICE FOR SEWING-MACHINES.

SPECIFICATION forming part of Letters Patent No. 524,340, dated August 14, 1894. Application filed February 23, 1894- Serial No. 501,205, (Nomodel.)

To all whom it may concern."

Be it known that I, FRANCIS ARTHUR MILLS,

a citizen of the United States, residing at' Philadelphia, in the countyof Philadelphia and State of Pennsylvania, have invented a new anduseful Improvement in Wax-Thread Heating Devices for Sewing Machines, ofwhich the following is a specification.

In shoe sewing machines using waxed thread, provisions have been madefor heating the thread for the purposeof keeping it soft and pliable asit is fed to the needle. In

such provisions the waxed thread has beenconducted to the needle throughtubes and subjected therein to the heat of a hot airdraft direct fromthe heating chamber of the waxing device. This hot air-draft Ihave foundperches and stiflens the thread and hardens it, and is objection ablefor the reason that such efiect tends to obstruct the feed of the threadthrough the eye of the needle and increases the resistance of the threadin the work.- The entire machine has also been heated to keep the waxedthread hot, but this is still more objectionable as it increases thewear of the working parts, burns out the oil of the lubricated parts andsubjects the l thread to a hardening action of the hot parts with whichit may be in contact in its passage from the wax-pot to the needle. Myimprovement avoids these objections; and my said improvement consists ina construction of the thread conduit whereby steam generated in thewater vessel used in heating the waxpot, is utilized for heating suchconduit exter nally and thereby heat the waxed thread by the radiationof heat within the tube through which the waxed thread passes to theneedle, keepingthe thread hot and pliable and the machine comparativelycool.

The accompanying drawings represent in Figure 1 a vertical section of somuch of a shoe sewing machine as illustrates the application thereto ofmy improvement for heating thread by steam. Fig. 2 shows the steamheated thread conduit in longitudinal section. Fig. 3 is a cross sectionof such conduit.

The wax-pot I prefer to arrange at the rear side of the machine and itmay be of any suit able construction as much as possible the through theheating conduit f to looper g and thence to the needle h. The threadconduit f is open at both ends and is arranged horizontally at the topof the machine so as to receive the thread from the tension device anddeliver it to the loop'er-arm. This thread conduit is inclosed by ajacket j which connects by a vertical pipe with the top of the water-potb so that the steam generated in the latter will constantly fill thisjacket and pass out through an opening Z at the front end of the jacketand thereby heat the thread conduit externally which heats the waxedthread therein by radiation.

j I prefer to make the thread conduit of an oval form in cross-sectionand place it with the oval standing vertical so as to divide the steamjacket into two longitudinal side spaces on, m, into which the steampasses from the vertical tube, as seen in Fig. 3. This constructiongives the advantage of confining the steam in contact with the oppositeoval walls of the thread conduit, and provides room for the slightvertical vibration of the thread within the conduit caused by the actionof the looper-arm in drawing the thread through it from the tensiondevice, preventing thereby contact of the thread with the hot walls.

It will be understood that in using steam a sufficient degree of heat isradiated through the walls of the conduit to give a uniform heat to thewaxed thread therein. It will also be understood thatI make no claimherein to any part or combination of parts of the sewing machineillustrated in the drawings, and that the construction whereby steam isused as the heating medium for the thread may be applied to machines ofdifferent constructions.

I claim as my improvement- 1. In a shoe sewing machine using waxedthread, a conduit for the thread having an in closing jacket or tube, incombination with a wax-pot having a water-chamber, a tube connecting thelatter with said jacket, and means for heating said chamber wherebysteam generated in the water chamber, used in heating thewax-pot, may beutilized for heating the thread-conduit, for the purpose stated.

, 2. In a shoe sewing machine using waxed thread, a conduit for thethread having an oval form in cross-section, in combination,

with an inclosing jacket divided longitudi- 1o nally by said oval threadconduit, a Water heating chamber and a tube connecting the latter withlongitudinal divisions of the jacket as described.

FRANCIS ARTHUR MILLS. Witnesses:

A. E. H. JOHNSON, A. ROLAND JOHNSON.

